Parallel Loop Model in C

• Note threads, shared, local

• main() {
  
  #pragma omp parallel for \
  shared(A)private(i)
  for( i=1; i<=100; i++ ) {
  . . .
  }
  }

A is shared

Parallel for

i=1

i=2

i=3

i=4

i=5

i=6

A

Several, e.g. 4, threads

created on entry

Iterations

scheduled

on threads

i is local

Threads

barrier at end

Threads either spin or

sleep between regions

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